Патент USA US2123341код для вставки
July 12, 1938. B_ OFFEN ‘ 2,123,341 DRYING METHOD AND APPARATUS ?led Nov. 26, 1935 my.2. N N INVENTOR. -, EfKN/MD OFFE/V BY 44M“ 91/ A TTORNEY. ' Patented July 12, 1938 2,123,341 UNITED STATES PATENT OFFICE 2,123,341 name METHOD AND APPARATUS ’ _ Bernard Often, Chicago, 111. Application November 26, 1935, Serial No. 51,563 8 Claims. (Cl. 34—24) This invention relates to drying. the insulating effect of this ?lm, the air supplied This application is a continuation in part of my co-pending application, Serial No. 6,453 filed February 14, 1935. Ol ‘ - The general object of the invention is to pro vide an improved method of and apparatus for drying materials of various description, particu larly freshly inked paper, textiles, chemicals, and the like. 10 ' It has been general practice in the drying art to dry materials by passing the materials under a hood or through a tunnel-like enclosure. 20 To must be at a relatively high temperature, in order that the heat may penetrate through the film to the inked surface and cause the solvents to vapor ize. According to the present invention, applicant breaks up and disperses this film by impinging thereagainst streams of air at high pressure and at high velocity. These streams of air also dis perse the small volumes of air contained between 10 the irregularities of the surface. The dispersion of the ?lm permits the drying air to heat the sur this tunnel-like enclosure is supplied air at pre determined temperatures to accomplish the re quired drying. The temperature of the air is varied, in accordance with the nature of the ma terial to be dried, the speed at which the material is to be dried, and the characteristics of the ma face directly and to convey vapors from the sur face, inasmuch as the drying air and the surface are thus brought into direct and intimate contact. ,By breaking up this ?lm and dispersing the air terial with relation to heat. content of solvents and water vapors, as well as ' between the particles, applicant continually brings to the printed surface air that has a small when freshly inked surfaces are passed through ' a desired temperature to assist in liberating the a tunnel-like enclosure or hood for drying, the solvents. In thisv way applicant e?’ects more air supplied thereto at predetermined tempera tures absorbs the solvents and water vapors given off by the inked surfaces. In addition, the air rapid liberation of the solvents, and through the dispersement of the volumes close to the inked surface, accomplishes the liberation and removal 25 acts as a medium to heat the surface to bring about a vaporization of the solvents and the water of the ink. The higher the temperature of the air supplied, the more readily will the of the solvents with a smaller air volume and also 25 with a lower air temperature. This lower tem perature is important since it does not soften some of the ingredients of the ink. Further, the turbulent action caused by the high pressure air brings the drying air more fre 30 quently in contact with the printed surface with the result that there is greater vapor absorption yond a certain point. For this reason, the tem- . by the air. This brings about more rapid and more .ef?cient drying, permits drying at lower" perature of drying air is maintained at a rela temperatures in view of the better contact with 3 35 tively low point, but large air volumes are used to sweep away from the surface ‘the vapor laden the surface, and permits the use of smaller, more air so that the vapors can readily vaporize into economical apparatus. A feature of the invention resides in supplying air not laden with solvents or water vapors. inked surface give up its solvents. 30 # In the drying of inked surfaces. certain ingredi cuts of the ink are materially softened by high temperatures. This becomes objectionable be ‘ The surface of a freshly inked web is rough and ' 40 irregular, due to the little ,crevices and spaces in between the various inked particles on the sur face. This inked paper travels at a high rate ofspeed, as for example,,between 500 and 1500 feet a. minute. At such a speed, and with the ir regular printed surface, the paper in traveling along, carries a film of air along with it. This > film, which blankets the paper, becomes saturated quickly with solvents or water vapors, and retards the liberation of vapors from the surface. In present-day practice, large air volumes are re quired to e?ect penetration of this film, so that air to material to be dried, removing‘the air after it has contacted the material,v and impinging 40 other air in. the form of high pressure,'high ve- T locity streams against the material. Another feature of the invention resides in sup plying air to material to be dried at a first point, removing ‘said air at a second point, moving. the- 4. material to be dried relative to said points, and impinging jets' of other air against the material. Another feature of the invention resides in dry .ing a material by impinging thereagainst air in the form of high pressure, high velocity streams.‘ 6 Another feature of the invention resides in sup .the freshly-introduced and relatively vapor-free plying a first volume of air to a surface to' be air may pick up solvents and vapor from the sur dried, impinging a second volume of air against face, and in order to maintain an overall low the surface in the form of high velocity high 65 vapor content in the air. Moreover, because of ‘ pressure streams, removing said volumes of air .. through pipe 29. The cooled air is fed through pipe 30, preferably equipped with a suitable pres face in the form of high velocity high pressure sure regulating valve 3|,’ to the manifold 32, streams, the temperature of said third air volume . whence it is discharged against the web 6, after being lower than that of the ?rst and second air the web has been subjected to the drying action after they have contacted the surface, and then impinging a third volume of air against the sur volumes. Neither, either or both of the ?rst and " second air volumes may be heated to hasten the drying of the material. >When warm air is used it has a tendency in some cases to soften the in 10 gredients of the material. By subjecting the ma terial to the action of a cooled third volume of air, applicant chills the material, or at least the surface of the'material, hardening thesame, and thus preparing the material for subsequent treat 15 ment. As will be understood, the expansion of the compressed air of the third volume brings about a chilling effect which‘ supplements that caused by the initially low temperature of the of air frompassage i3 and jets 21. ,\Air is 'dis- . charged from manifold 32 through jets 33 in a plurality of high pressure high velocity streams which chill the web, or rather the inked surface of the web, and thus prepare it for further treat 10 ment. \ Fig. 2 illustrates the application of the inven tion to a drier of the tunnel type. Heated air is introduced to the tunnel 40v through supply duct 4|, and after contact with material 42, to be dried, is removed through duct 43. Compressed air is supplied through pipe 44, corresponding to pipe 24 of Fig. 1, to manifold 45, whence it is dis charged in the form. of a plurality .of high third air volume. . Other objects, features and advantages of the .velocity high pressure streams through jets 48. 20 In the drying of chemicals on trays or conveyors _ invention will be more apparent from the fol lowing description of the invention to be read in of any form, to which applicant's invention is connection with the accompanying drawing in suited, it is customary to provide a heating means which: in the tunnel. In the drying of textiles it is Fig. 1 diagrammatically represents one form of usually necessary to provide a hot plate over applicant's invention, utilizing a drying hood; and which the material passes. Applicant's invention Fig. 2 is a diagrammatic view'illustrating the supplements these and similar arrangements, and application of the invention to a tunnel drying does not con?ict with them in any respect. system. - Turning now to the drawing, 5 represents gen erally a drying hood similar to that disclosed in my co-pending application, Serial No, 6,453, ?led February 14, 1935. Under the hood is passed a web of paper 6, or the like, to be dried, carried on rollers 1. Air is drawn into the system by fan I, driven by motor 9, and is supplied to hood I through duct l0. If desired, the intaken air may be heated by heater ll. Inside the hood 5 air is supplied to discharge port l2 through ' passage l3. ‘The air discharged from port l2 If desired, drying maybe affected solely by the high pressure high velocity air streams and heating. . Since many modi?cations maybe made in the invention without departing from the scope there of, it is intended that the foregoing description and accompanying drawing be regarded as illus trative only, applicant limiting himself only as indicated in the appended claims. I claim: ‘ 1. A method of drying a printed surface of a web consisting in passing the web through a 40 contacts the web 6, and is drawn off through ex-. "con?ning hood, discharging a main volume of haust ports i4, and discharge duct i5, under the air within the hood in a condition capable of ef-, in?uence of discharge fan It, driven by motor I1. 'fecting drying of a freshly printed surface, dis ll represents a dehydrator, iii an air cleaner, charging a. secondary smaller volume of air with in the hood at a velocity much greater than that "an air heater, and 2| anyair pre-cooler. Com pressed air is supplied to dehydrator l8 through. of the velocity of discharge of the main volume, the secondary volumeibeing directed at the web pipe v22, from any suitable source. The com pressed air, dehydrated and cleaned, is divided at \ to break up ?lm forming at the printed surface.v 2. A method of drying a printed web consisting 23, part of the compressed air being ‘routed through heater 20, and part of the compressed in passing the web through a con?ning hood, discharging a main volume of air within the hood air being routed through pre-cooler “2|. Com ressed air from heater 2|! is passed through pipe ,4, equipped with a pressure regulating valve‘ 25, for drying the web, simultaneously discharging a to mani‘foldm? disposed within the hood 5. Air iii-om manifold 26 is discharged at high velocity and at high pressure through a plurality of jets I1, directed against web 6. The high pressure, considerably higher than the discharge velocity bigh velocity air streams break up the ?lm of solvent laden air which forms a blanket ‘along the surface of web 6 and thus facilitates drying of the web. Further, the high pressure air dis pers'es the minute air volumes limmediately sur rounding the small particles of ink applied to the surface, and thus permits contact of the fresh air with the large exposed area offered by the small ink particles. This direct and effective‘ ‘contact and continual change vof the air im -mediately in contact with the small inked particles, make for rapid and ‘efficient drying. The air introduced through jets 21 is passed from the'hood through discharge duct is. second volume of air within the hood at a velocity of said main volume of air in the form of small 55 streams of- air impinging forcefully against the web, and relieving air from the hood. - 3. The method of drying a web which consists in passing the web through a con?ned space, ad mitting within said space air in a condition capa ble of effecting drying of the web and passing such“. air adjacent said web, withdrawing said air from the vicinity of the web and from said space after it has passed adjacent said web and exerted a drying action thereon, and discharging a sec ondary smaller volume of air within said space at a velocity much greater than that at which said ?rst mentioned air is/passed adjacent the web, the secondary air volume being directed at and impinged against the web to prevent the 70 formation of film at the web surface or to break Air in the cooler 2| is cooled by a cooling . up such ?lm if formed. medium introduced through pipe 28 and removed ' ' BERNARD OFFEN.